94 Transmission Possible Issue

Greetings all, I hope everybody had a safe and good Holiday. Unfortunately the new years doesn't seem to be kind to me here, as it seems I might have a possible transmission issue.

94 Caprice 9C1, 137K on it.

I was driving on the highway, at ~55mph and all of a sudden it just seemed to decrease in speed fairly drastically, as the car then just started to feel really heavy. It also basically 'revved' up pretty drastically as if the engine was losing grip with the transmission.

So I get off the highway, which so happened to have a extremely steep hill. Now by this time, it sounded like I was revving it up like crazy.

Then on the straight road, it seemed to be going fine up to 20 mph. Sped up a bit, then the revving again, and it seemed to just feel heavy again. Back down to 20, and while trying to stay consistent at this speed, the engine started to rev up pretty drastically.

So even at a constant speed, it was essentially losing 'power'. Pulled over, cool it a bit, restarted. Also, when I accelerated up to 35mph, it seemed to pull ok, but was jerking still while moving up in speed (this jerk I felt too earlier when trying to accelerate and also decelerating. Then as like when I was going 20, it just started losing its 'grip' with the transmission again, forcing me to back downwards.

I noticed in the morning, when I put it into D, from R getting out of the driveway, it didn't have the push you normally have under the idle acceleration. Also, when first got the car last summer, it essentially had no transmission fluid in it as it was sitting there for 4 years and there was a leak of sorts from a slight leak. (I'm going to have to try to confirm what it was with my mechanic). When I had the car serviced, he basically said to just monitor it, which has been fine. But to fix it would likely require it to be opened up and it didn't seem to be a significant cause for concern. .

After pulling over, the fluid seemed fine, very light clear purple, and a chemically smell, but not really burnt (but it I guess it could pass for a burnt smell). I don't floor it hard or anything, except for the occaisional time when I do a donut in the snow or just mash when cornering (which too is relatively rare). I got the car at 129K so its more of a evening/weekend car.

I was wondering if anybody had any suggestions if it is likely the transmission (which I'm sure it is) and what it might more specifically be. Also, would it be wiser to go to a general mechanic first, or a transmission shop directly.

Thanks in advance!

Hard to tell without going for a ride with you but 3-4 clutch pack failure is fairly common. In which case first and second work fine so it would drive OK till it tried to shift into 3rd at which point it would slip badly.

There is good news and bad news, this tranny CAN be solid and reliable, bad news is most shops can not match GM's quality and a relative few can mae them work behind big power.

For just a driver I would consider the GoodWrench remanufactured unit unless a local shop has specific good track record with this exact tranny in a similar application that you can verify for years of use. I know that sounds extreme but a LOT of us have been burned by incompetent local shops even ones that did great work on other trannies or that had short term happiness from customers with this tranny.

A tranny is not like an engine, a badly built one might last 6 months or a year before it falls apart which is why long term feedback is critical.

Hard to tell without going for a ride with you but 3-4 clutch pack failure is fairly common. In which case first and second work fine so it would drive OK till it tried to shift into 3rd at which point it would slip badly.

There is good news and bad news, this tranny CAN be solid and reliable, bad news is most shops can not match GM's quality and a relative few can mae them work behind big power.

For just a driver I would consider the GoodWrench remanufactured unit unless a local shop has specific good track record with this exact tranny in a similar application that you can verify for years of use. I know that sounds extreme but a LOT of us have been burned by incompetent local shops even ones that did great work on other trannies or that had short term happiness from customers with this tranny.

A tranny is not like an engine, a badly built one might last 6 months or a year before it falls apart which is why long term feedback is critical.

Thank you for the response. I definitely read alot of the issues with the commonality of failures (just mainly due to the sheer torque on these cars) and the issue with rebuilt transmissions as its better to just spend more for a 'new' one in the long run.

Just to confirm, would you recommend me just taking it to a mechanic first to confirm or a tranny shop to confirm? I would defnitely just tell them that I would pay for a inspection separately (to avoid them pressuring me to make the sale).

Also, would entail one to go to GM to buy the transmission and have it installed at the dealership? Or can I just go to a reputable shop and ask them to order it from the dealer (to save a bit on labor and with transmission guys having more of a specialty skill in it).


Is it common for the engine to start revving faster at a constant speed, with a 3-4 clutch problem? Not sure if this helps, I ran over a icy snow bank at a fairly high speed on New Years as I couldn't see due to some fog and did notice a bit of a sluggishness after (not sure if that could somehow cause the transmission to 'pop')

Duane is correct. The factory remanufactured unit is a solid way to go. You get a good transmisison, with all the latest upgrades, and a 3-year/36,000 mile global warranty. If you do not have confidence in your local transmission shops, that might be a safe, albeit more expensive, way to go. Warranty will require you to install a factory reman or new torque converter with that transmission, and to either replace the radiator or flush the transmission cooler and lines before installation. That is prudent practice no matter what you do to resolve the problem.

However, before going that far, some diagnosis would also be prudent. Connecting a capable scanner such as a Tech II or MT-2500 would reveal any stored trouble codes. A test drive with the scanner might reveal any solenoid, switch, or pressure transducer problems. A test of line pressure with a mechanical gauge is also a good diagnostic aid, and if the line pressure is a problem, that might be remedied with as little as removing the pan for repairs.

I had one that did exactly the same thing, and the cause was simply a failed snap ring on the PR valve in the pump body, repaired in under an hour by simply removing the pan:

http://mysite.verizon.net/strey/files/4L60PumpPressureControl1.jpg

You might even be lucky enough to discover that because of the clean, fresh oil you installed the trans is getting cleaned out and the filter is clogged.

the point is that before condemning the transmission, diagnosis would be worthwhile.

You might even be lucky enough to discover that because of the clean, fresh oil you installed the trans is getting cleaned out and the filter is clogged.

the point is that before condemning the transmission, diagnosis would be worthwhile.

Thank you for the info. I also just noticed as I backed the car away, there was a leak in the transmission fluid (a neat little puddle, still purple). So I warmed it up a bit, down to D, then back to P, and checked the fluid, it was where it should be.

I also confirmed it was the front seal pump that likely required fixing but was not done so back then. So I am guessing that's what it might be now likely causing a leak, loss of fluid or pressure. Now of course, dummy me drove it home another 3 miles or so likely making it worse.

Could this also have been exasperated by a physical external blow (ie running over a hard, very low ice bank...like a speed bump?)

No, but I can possibly accept that such a bump could have dislodged the filter (and therefore, the pump pickup tube) enough to allow the pump to suck some air and not produce adequate pressure.

Stranger things have happened, even to me. I had a Fiero which would intermittently not produce adequate fuel pressure after an accident. It turns out the fuel pump was dislodged from the discharge tube by the G-forces of the impact, and it took a lot of head scratching to find that one:

http://mysite.verizon.net/strey/files/FuelPump1.jpg

All that is just further excuse to diagnose the problem before ordering that new transmission.

Hard to tell without going for a ride with you but 3-4 clutch pack failure is fairly common. In which case first and second work fine so it would drive OK till it tried to shift into 3rd at which point it would slip badly.

There is good news and bad news, this tranny CAN be solid and reliable, bad news is most shops can not match GM's quality and a relative few can mae them work behind big power.

For just a driver I would consider the GoodWrench remanufactured unit unless a local shop has specific good track record with this exact tranny in a similar application that you can verify for years of use. I know that sounds extreme but a LOT of us have been burned by incompetent local shops even ones that did great work on other trannies or that had short term happiness from customers with this tranny.

A tranny is not like an engine, a badly built one might last 6 months or a year before it falls apart which is why long term feedback is critical.

That was right on. The 3-4 clutch pack has failed. Very good call=] I was fortunate to find a independent shop very close to my house, who has actually has gotten quite a lot of them in his shop (he also has it listed on his web site which I only found out afterwards). Very friendly guy/owner and was mentioning this was a common failure that he's worked on often.

The total cost is about $1200 Cdn (Includes the removal/opening charge of ~$300, TPS, flush, and I also believe a gasket for the engine as it was slightly leaking oil)

So looks like based on my budget, cash flow requirements for this year (most specifically the need to save up for the 'Ring' otherwise would get my butt handed to me esp since she doesn't understand my fascination with these cars) and that I have another caprice & van sitting around (not insured right now though), I figure this seems to be a good option for now. Also, I drive ~5-7K miles/yr so a shorter term fix would be more viable.

My ultimate goal once I'm settled a bit more with everything in a few years and the benefit of a duo income, I would likely save a decent chunk of $, and then try to do 'build' a more complete car including the transmission, so I'm willing to take that risk for now (as it might be a totally different caprice). Though ideally I would have definitely liked to have followed your advice on the GoodWrench Remanufactured one. Well, hopefully things turn out.

Thank you and to Blue Bowtie for the helpful responses.


I also just have a few follow-up questions:

1) I was wondering, as I didn't get a Check Engine Light on, would a scan have picked it up before the 'trouble occured'? (He scanned once it 'broke' confirming it)

2) Also, is it worth it to get some kind of shift kit while the trans is out and being worked on? Just from what I've read, a shift improver kit (B&M?) improves reliability and performance.

How about a transgo stage 2 shift kit? I'm thinking probably not needed as it might cause more strain/reduced relability? I dont' generally drive it too hard and the engine/exhaust is not upgraded in anyway.

A big part of what the Transgo kit does is solve inherent flaws, done right they help transmission life. This tranny does NOT like to be shifted hard even on a car like mine a quick shift is the goal, not a hard one.

On your '94 (and later years) the PCM will actually cut ignition/fuel briefly to ease the transition, making shifting a little easier on the trans and driveline. It's completely imperceptible.

The PCM will set an error code if it detects a difference in engine RPM and output shaft speed beyond a reasonable tolerance. Since the torque converter is supposed to allow slip during acceleration, so the PCM might not lock a code until the trans slips at cruise speeds and loads.

As advised, an upgrade kit will typically address some issues common with a given transmission.

If it isn't too late, you might want to ask the rebuilder about removing the 3-4 clutch pack return spring cages, sizing the front end clutch spacer for the low end of clearance, and making sure it has at least a 6-disc clutch and steel set (some came with 5 and an extra thick spacer).

The black caged steel return springs in question are in the middle of the photo:

http://mysite.verizon.net/strey/files/4L60EInputDrumClutchesLg.jpg

A modified TCC boost valve is a good idea, either by replacing the valve spool or modifying it on a grinder.

A new separator plate is about the best $20 you'll ever spend inside a trans.

On your '94 (and later years) the PCM will actually cut ignition/fuel briefly to ease the transition, making shifting a little easier on the trans and driveline. It's completely imperceptible.

The PCM will set an error code if it detects a difference in engine RPM and output shaft speed beyond a reasonable tolerance. Since the torque converter is supposed to allow slip during acceleration, so the PCM might not lock a code until the trans slips at cruise speeds and loads.

As advised, an upgrade kit will typically address some issues common with a given transmission.

If it isn't too late, you might want to ask the rebuilder about removing the 3-4 clutch pack return spring cages, sizing the front end clutch spacer for the low end of clearance, and making sure it has at least a 6-disc clutch and steel set (some came with 5 and an extra thick spacer).

The black caged steel return springs in question are in the middle of the photo:

A modified TCC boost valve is a good idea, either by replacing the valve spool or modifying it on a grinder.

A new separator plate is about the best $20 you'll ever spend inside a trans.

I had gotten it fixed (it was too late by the time I had gotten this). I did get a shift kit put in. He referred to it as a junior shift kit, as I didn't want the one with the firmer shifts. The help and suggestion is greatly appreciated, and can possibly used in the future.

I'm taking it back in tomorrow or Fri just for a follow-up. I did notice that during acceleration, it does feel a bit more sluggish of the start then before (have to press the pedal harder), and seems to be revving higher before shifting to 2nd. And seems to rev high on 2nd before shifting to third. But going at higher speeds, it definitely has a stronger and more response pull then before.

Would this be normal? Or maybe some damaged caused by driving it the few miles once the clutch damaged.


Additional Question/Issue:

Also, the powersteering fluid is leaking (from the line somewhere). I'm not sure if its the high pressure or the low pressure, but the seems to be coming out around where the radiator is at the bottom. Whenever I drive it, it leaks, most specifically, it drips in the section where it curves and appears to have some kind of clip around it.

I felt it there, but there doesn't appear to be a crack or anything, so it looks like its running out from where the radiator is, but running along the line and dripping once hitting the bracket.

Once topped up, the power steering is fine, no noise, easy to turn.

I'm guessing it might have been caused by when I ran over the speed bump of ice. Is this something easy to fix? Or expensive to replace? I tried doing a search but couldn't come up with anything.

If installed right the real shift kit does not have particularly firm shift, quick and positive yes but jarring is a BAD BAD thing despite how often it is done.